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Damian Skeeles · February 2nd 04, 02:27 PM posted to uk.transport.london

(Ian Davidson) wrote in message m...

The card is a transponder. The RF energy emitted by the reader is
received in the antennae (coil) around the edge of the card. This
powers the card, and the presence of RF at the correct frequency wakes
up the trasmit circuitry and it transmits its coded information. If
you hold the card up close to a very strong light source you should be
able to see the component parts. If you decide to trim your card be
prepared to trash ity and buy a new one!

I suspected as much. I might sit tight on that idea - no doubt
there'll be LU-branded smart-clothing (mittens?) within a couple of
years :-)

Thanks to everyone who replied!